Problem: A rectangle is $3$ inches long. The rectangle is also $5$ inches wide. What is its perimeter?
$3\text{ in}$ $5\text{ in}$ The perimeter is the total length of all the sides of the shape added together. Add up the lengths of the sides: $ \text{perimeter} = {5} + {3} + {5} + {3} $ $ \text{perimeter} = 16\text{ in} $